>There are some technical tests used on Dalmations that show promise in
>testing ferret hearing, but my favorite "cheapie" is the vacuum cleaner
>test (turn it on and see if you get a reaction).
 
The vacuum test doesn't always work - my deaf little Twist loves to play
with the vacuum (admittedly odd, but ACSL can hear and LOVES to count coup
on the vakoom), I'm not sure if it is the light or the vibration.  And if
your house is on piers or over a crawl space or basement, there is quite a
bit of physical vibration produced by the vacuum.
 
We tried jingling a large set of keys and using a throw can, but were still
unsure if she was deaf.  Our veterinarian checked it out for us the next
time we came in by using a dual set of tuning forks.  (His techs now thank
us every time we come in - he's been sneaking up on them with tuning forks
vibrating to see them jump!) This isn't necessarily a thorough test either,
but we surely know that she is at least deaf to a middle "C".  Twist slept
through the whole process and went immediately back to sleep after we woke
her up to try again.  Zero reaction.
 
Maybe if you want to find out if your ferret is deaf and to what extent,
you should make an appointment with your local piano tuner?
[Posted in FML issue 2764]